Blasting cap composition



pletely as do fulminate and azide.

Patented Jan. 4, 1938 UNITED STATES PATENT eras'rmo CAP COMPOSITION ware No Drawing.

12 Claims.

This inventionrelates to an improved explosive composition and blasting caps including the improved composition as a charge. The improved explosive composition may be used alone or as an initial detonating composition in blasting caps.

Heretofore blasting caps have been loaded with various initial detonating compositions, e. g., mercury fulminate, diazodinitrophenol, mixtures of these with potassium chlorate, lead azide, alone or mixed with trinitroresorcinate, etc., or the blasting caps have been loaded with a non-initiating base charge, e. g., tetryl or trinitrotoluene, over which is loaded an initiating charge of mercury fulminate or diazodinitrophenol, or mixtures thereof with potassium chlorate.

A blasting cap containing diazodimtrophenol, or a mixture thereof with potassium chlorate, either as the sole charge or as a top charge over tetryl or trinitrotoluene, has the great advantage over caps containing mercury fulminate that it withstands, without failing to detonate, much larger percentages of moisture. This is important, because common, or open end blasting caps, intended for firing by a fuse, have to withstand storage underground in moist atmospheres.

A disadvantage of diazodinitrophenol, as ordinarily produced, is that it has a low density and comprises needle-shaped crystals, which cause the substance to mat together and fail to flow readily through the holes of the charging plate of the cap loading machines. Such disadvantage of needle-shaped crystals has been overcome recently, for example by the process described in United States Letters Patent #1,952,591 for production of diazodinitrophenol comprising rounded grains which will flow readily. However, even when produced in the above manner, diazodinitrophenol suffers from the disadvantage of being of low density, e. g., about 1.63 as compared to 4.80 for lead azide, and 4.42 for mercury fulminate, and fails todrop through holes in charging plates as rapidly or as com- Naturally, addition of the usual potassium chlorate, of density about 2.37, is of little assistance in this connection, since the density of the mixture will be between 1.63 and 2.37, and no substantial increase in density will result from the addition of this oxidizing agent.

It has been discovered that a mixture of diazodinitrophenol and a heavy metal oxidizing agent improves markedly the loading properties in the manufacture of blasting caps, as compared to Application September 17, 1935,

Serial No. 40,927

the use of diazodinitrophenol alone for such purpose. Varying proportions-of diazodinitrophenol and the heavy metal oxidizing agent, but preferably about equal parts of each or a ratio of '75 parts of diazodinitrophenol to parts of the heavy metal oxidizing agent may be used.

As the heavy metal oxidizing agents to be mixed with the diazodinitrophenol for the production of flowable compositions for loading blasting caps there may be used, for example, barium nitrate, of a density of about 3.244, lead nitrate, of a density of about 4.53, barium peroxide, of a density of about 4.96, etc.

This improved diazodinitrophenol-heavy metal oxidizing agent mixture may be used alone in common and electric blasting caps, or in such blasting caps an explosive nitro compound base charge, such as, for example, tetryl or trinitrotoluene, not in itself an initiating explosive, may be used and there may be superimposed on such base charge an initiating charge composed of the heavy metal oxidizing agent-diazodinitrophenol composition. For example, into the cap shell a base charge of 0.16 g. of tetryl may be pressed and then an initiating charge of 0.40 g. of a /50 mixture of barium nitrate-diazodinitrophenol may be pressed therein.

It has been found that the sensitivity to friction is much less for the mixture of heavy metal oxidizing agent-diazodinitrophenol than is the sensitivity to friction of the usual mixture of diazodinitrophenol and potassium perchlorate. example, in a test in a pendulum friction machine, with a mixture of diazodinitrophenol and potassium chlorate in a ratio of 75/25, there was no explosion with a 500 g. weight, but explosion with a 1000 g. weight, whereas with the improved composition comprising, for example, diazodinitrophenol and barium nitrate in a ratio of 75/25 there was no explosion with a 1000 g. weight and explosion only with a 2000 g. weight. This shows that the improved composition is far less sensitive to friction in handling and loading, and hence safer to use.

It is known that heavy metal nitrates have been used heretofore in compositions of various kinds for the manufacture of percussion caps, but not in connection with diazodinitrophenol. Such percussion cap compositions are loaded in a wet or pasty state, and are not required to flow in a dry state uniformly and completely through charging plates such as are used in the manufacture of blasting caps. Such percussion cap compositions are unsuitable for the manufacture For consisting of diazodinitrophenol about 75% and a heavy metal oxidizing agent about 3. An explosive composition for blasting caps consisting of diazodinitrophenol about and.

a heavy metal oxidizing agent about 50%.

4. A detonating explosive composition for blasting caps consisting of diazodinitrophenol and barium nitrate.

5. An explosive composition for blasting caps consisting of diazodinitrophenol and. lead nitrate.

6. An explosive composition for blasting caps consisting of diazodinitrophenol and. barium peroxide.

7. An explosive composition for blasting caps consisting of diazodinitrophenol about and barium nitrate about 25%.

8. A blasting cap containing as detonating explosive charge a mixture consisting of (11212061- nitrophenol and a heavy metal oxidizing agent.

9. An electric blasting cap containing as explosive charge a mixture consisting of diazodinitrophenol and a heavy metal oxidizing agent.

10. A blasting cap adapted for firing by fuse, comprising a cap shell and an explosive charge consisting of a mixture of diazodinitrophenol and a heavy metal oxidizing agent.

11. An electric blasting cap containing as explosive charge a mixture consisting of diazodinitrophenol and barium nitrate.

12. A blasting cap adapted for firing by fuse, comprising a cap shell and an explosive charge consisting of a mixture of diazodinitrophenol and barium nitrate.

ANSON B. NIXON. Administrator 0,1 the Estate of Lloyd H. fisher,

Deceased. 

